Support mechanism for optical block in optical disc drive apparatus

Abstract

A support mechanism for an optical block provided with an optical head, wherein provision is made of a reference shaft and a support shaft attached in parallel to the reference shaft, the optical block being supported between the reference shaft and the support shaft in a movable manner by positioning rotational members which are provided at one side of the optical block and which are for positioning and guiding at two locations along the axial direction of the reference shaft and by supporting rotational members which are provided at the other side of the optical block and which are for supporting and guiding the optical block at two locations of the support shaft corresponding to the two locations along the axial direction of the reference shaft. The supporting rotational members for supporting the optical block with respect to the reference shaft are elastically supported so as to be able to approach and move away from the optical block, so even when there is a fluctuation in the distance between the reference shaft and the support shaft supporting the optical block, the occurrence of rotational motion about the direction along the direction of movement of the optical block can be suppressed.

What is claimed is: 
     
       1. A support mechanism of an optical block in an optical disc drive apparatus provided with a reference shaft, a support shaft positioned substantially parallel to the reference shaft, and an optical block which has an optical head and which is supported between the reference shaft and the support shaft by the support mechanism so that the optical block moves along an axial direction of the reference shaft substantially in parallel with the reference shaft, the support mechanism comprising: at least two positioning rotational members provided at a positioning side of the optical block for positioning and guiding the optical block at two positioning locations along the axial direction of the reference shaft,   at least two supporting rotational members provided at a supporting side of the optical block for supporting and guiding the optical block at two supporting locations along the support shaft, and   a roller support member including an attachment portion attached to the optical block and wings which elastically support the supporting rotational members so that the supporting rotational members approach and move away from the optical block and so that when any one of the supporting rotational members is moved toward the optical block, the wing supporting that supporting rotational member elastically presses that supporting rotational member away from the optical block.   
     
     
       2. The support mechanism as set forth in claim 1, wherein each positioning rotational member includes a pair of rollers gripping the reference shaft and wherein each supporting rotational member includes a pair of rollers gripping the support shaft. 
     
     
       3. The support mechanism as set forth in claim 1, wherein the positioning rotational members include rollers attached rotatably to shafts and the supporting rotational members include rollers attached rotatably to shafts. 
     
     
       4. A support mechanism of an optical block in an optical disc drive apparatus provided with a reference shaft, a support shaft positioned substantially parallel to the reference shaft, and an optical block which has an optical head and which is supported between the reference shaft and the support shaft by the support mechanism so that the optical block moves along an axial direction of the reference shaft substantially in parallel with the reference shaft, the support mechanism comprising: at least two positioning rotational members provided at a positioning side of the optical block for positioning and guiding the optical block at two positioning locations along the axial direction of the reference shaft;   at least two supporting rotational members provided at a supporting side of the optical block for supporting and guiding the optical block at two supporting locations along the support shaft, each supporting rotational member including a pair of rollers which grip the support shaft;   a roller support member formed by a plate-like spring material and having elastic displacement portions at two wings of an attachment portion attached to the optical block, the supporting rotational members being attached at roller holders attached to the elastic displacement portions, the wings elastically supporting the supporting rotational members so that the supporting rotational members approach and move away from the optical block and so that when any one of the supporting members is moved toward the optical block, the wing supporting that supporting rotational member elastically presses that supporting rotational member away from the optical block.   
     
     
       5. The support mechanism as set forth in claim 4, wherein spaces for allowing elastic displacement of the elastic displacement portions are present between the elastic displacement portions of the roller support member and a surface of the supporting side of the optical block. 
     
     
       6. The support mechanism as set forth in claim 1, wherein each supporting rotational member includes a pair of rollers gripping the support shaft and is attached to a roller holder attached to elastic displacement portions on the wings of the roller support member so that shafts of the rollers form substantially 45° angles with respect to a plane including an axial center of the reference shaft and an axial center of the support shaft. 
     
     
       7. The support mechanism as set forth in claim 1, wherein the optical block is connected to a movable portion of a linear motor through a connecting arm and is moved and operated along the reference shaft by the linear motor. 
     
     
       8. A support mechanism of an optical block in an optical disc drive apparatus provided with a reference shaft, a support shaft positioned substantially parallel to the reference shaft, and an optical block which has an optical head and which is supported between the reference shaft and the support shaft by the support mechanism so that the optical block moves along an axial direction of the reference shaft substantially in parallel with the reference shaft, the support mechanism comprising: at least two positioning rotational members provided at a positioning side of the optical block for positioning and guiding the optical block at two positioning locations along the axial direction of the reference shaft;   at least two supporting rotational members provided at a supporting side of the optical block for supporting and guiding the optical block at two supporting locations along the support shaft; and   a roller support member provided at a center of the supporting side of the optical block, the roller support member having a U-shaped attachment portion attached to an attachment surface of the supporting side of the optical block and having an elastically displaceable roller holding portion provided at each of two wings of the attachment portion,   wherein each supporting rotational member includes a roller bearing having a concave surface formed at a periphery of the roller bearing, the concave surface abutting against the support shaft, each supporting rotational member further including a bearing shaft supporting the roller bearing, the bearing shaft having a top end and a bottom end engaged with and held by slits formed in each roller holding portion of the roller support member, each roller holding portion holding each supporting rotational member, such that when the roller holding portions are elastically biased toward a side surface of the optical block, the roller bearings abut against the support shaft and position the optical block against the reference shaft by an elastic recovery force of the roller holding portions.   
     
     
       9. A support mechanism of an optical block in an optical disc drive apparatus provided with a reference shaft, a support shaft positioned substantially parallel to the reference shaft, and an optical block which has an optical head and which is supported between the reference shaft and the support shaft by the support mechanism so that the optical block moves along an axial direction of the reference shaft substantially in parallel with the reference shaft, the support mechanism comprising: at least two positioning rotational members provided at a positioning side of the optical block for positioning and guiding the optical block at two positioning locations along the axial direction of the reference shaft;   a roller support member provided on a supporting side of the optical block, the roller support member having an attachment portion attached to an attachment surface of the supporting side of the optical block and having an elastically displaceable roller holding portion provided at each of two wings of the attachment portion,   at least two supporting rotational members provided at the supporting side of the optical block for supporting and guiding the optical block at two supporting locations along the support shaft, each supporting rotational member including a roller bearing and a bearing shaft, the roller bearing having a concave surface formed at a periphery of the roller bearing, the concave surface abutting against the support shaft, the bearing shaft supporting the roller bearing and having a top end and a bottom end held by each roller holding portion of the roller support member, whereby when the roller holding portions are elastically biased toward a side surface of the optical block, the roller bearings abut against the support shaft and position the optical block against the reference shaft by an elastic recovery force of the roller holding portions.